Fetal spine findings on MRI and associated outcomes in children with open neural tube defects

The purpose of this study is to determine the relationship between abnormal fetal spine findings on MRI and adverse outcomes in children with open neural tube defects.

This was a review of pregnancies complicated by myelomeningocele referred for fetal MRI from 2001 to 2007 and followed postnatally at a spina bifida treatment center. MRI scans were reviewed to determine lesion level (T-L2, L3-4, or L5-S), interpediculate distance (≤ 10 or > 10 mm), vertebral segment span, and presence or absence of covering membrane. Ambulation was assessed in children 3 years old or older. Bladder dysfunction was termed as high-risk if renal damage was present or if urodynamic studies indicated increased risk for renal damage. Statistical analyses included chi-square, Mantel-Haenszel test for trend, and logistic regression.

MRI was performed in 36 pregnancies with fetal myelomeningocele at a mean (± SD) of 27 ± 6 weeks, with subsequent delivery at 38 ± 1 week. Outcomes were assessed at 3.2 years (range, 2.4-5.1 years), and 23 children were 3 years old or older. Higher lesion level was associated with dysphagia: T-L2, 50%; L3-4, 45%; and L5-S, 13% (p < 0.05). The absence of covering membrane was associated with scoliosis (36% vs 0% with membrane present) and with high-risk bladder dysfunction (71% vs 36%; both p < 0.05). Higher lesion level, larger segment span, and interpediculate distance greater than 10 mm were associated with full-time wheelchair use (all p < 0.05).

In fetuses with myelomeningoceles, higher and larger lesions on MRI were significantly associated with full-time wheelchair use. High lesion level was associated with dysphagia. The absence of a covering membrane was associated with scoliosis and high-risk bladder dysfunction.